What is maximum cable length and Slaves allowed on Serial Ports of Modicon M238 Controller.
1.The maximum cable length on serial link port1 and port2 of Modicon M238 controller is 30m without isolator TWDXCAISO and 1000m
with isolator TWDXCAISO and maximum 31 Slaves on RS485 network without repeater and maximum 256 Slaves with repeater.
2.The maximum cable length for Serial port1 for RS232 line is 15m . If you are using RS-232 devices, you can have only two devices total,
regardless of how they are configured. RS-232 is not multi-drop.
Refer to attached document for Modbus cabling system of Modicon M238 controller.